Core making machine



cons MAKING MACHINE Filed A ril lz, 1945 3 Sheets-Sheet 1 j o. H. W060 ETAL 2,409,330

Patented Oct. 15, 1946 UNITED STATES PATENT OFFICE GORE David Howardv Wood, Barnt Green, and Herbert James Roe, Knowle, England Application April 12, 1945', Serial No. 587,988 In Great Britain November 20, 1943 2. Claims. (01. 22-1o The invention.v relatest'o core making machines or, as they are" perhaps more: frequently called, coreblowing; machines of the kind in which the divided material of which the cores are to be made; usually sand, is fed': into" a container or magazine above a table onwhichthe core box is placed and an air stream is charged into the container or magazine under pressure and: the sand is blown or forced through'apertures in the base plate of the: magazine: and. into correspondingv apertures in the core'box' leading to the cavity or cavities in which the core or cores is tobe formed.

The improved machine: according to this invention provides a combined pneumatic and-hydraulic arrangement for movingthe" sand container or magazine unit to any desired distance within its range from the table, which arrangement gives a very smooth and even movement.

The improved machine also has a convenient and simple means-for imparting at small, evenmovement to the table towardsthe magazine for clamping thev core box, placed upon. itsecurely to the underside of the container or magazine.

Other featuresof the machine will be pointed out in the: following v description; of a preferred embodiment whichis illustrated inthe appended: drawings; and the scope of the protection desired is: defined-in the claims hereinafter appearing:

Figure 1 is a front view of the machine with parts broken. away, and a sand feedh'oppe'r and a motor omitted from thetop-of thefigure.

Figure 2 is a side view thereoi; but showing part of the hopper.

Figure 3 is a sectional view of' part of the base of the machine showing. themeansior moving. the table.

Figure 4 is a part sectional view oi theblowing? container or magazine.

In this embodiment of the machine: i is the base casting, H- is the blowing container or'maga' zine for the sand-and I2 is the hopper by which the sand is fed in the desired amounts; to: the container or magazine; I l. Thetable which. supports the moulding boxes of various sizes is referred to by'the numeral i3, and the substantial pressure plate and sand delivery plate-at the base of the magazine, which is opposite the table and co-operates with it. in the clamping ofthe box, is. marked Id.

Forf'this purpose: of clamping the box. thetable I 3' is adapted for a small upward. movement with respect to the substantial bed. or casting; Hi the means for this purpose comprising. a. piston l5: moving; in a. cylinder l6: above which. compressed air maybe forcedto drive down the pistonso-that its rod I! will rock a bell-crank lB-to one arm of which it is connected and the other arm of the bell-crank is preferably equipped with a roller 19 and engages an end disc 20 closing. a tubularplunger 2! in a guide 22, and the top of this plunger is flanged andbolted. to the underside of the table [3. A spring. 23: around the piston rod in the cylinder |6- assists the weight of the table in returning. the parts and the piston [5. The surface of the table is preferably provided, with removable, hard steel plates 2H bolted in position.

On. each side of the table l3 rigidly secured in the bed or base casting H1 is an upstanding pillar rod 24 and upon these two pillars 24 is suitably guided the sand container or magazine II. The guiding means comprise a pair of split bearings i'ii'projectingi laterally from the sides of the bodyof the magazine and av second pair of split bearings 26-near the lower part of the magazine, both pairs being capable of sliding on the pillars 24 and. both being equipped with clamping means so that .they can be fixed on the pillars in order to set the magazine at thedesired height.

The clamping means shown comprises a screw rod 21 anchored-in a lug 28 of a split bearing and working in a, tapped bore in a second lug 29 to draw the twotogether when the handle 30 is appropriately turned. The sand magazine H is directly over the table i3 and the. pressure plate M which also acts as a. sand delivery plate, at the base of the magazine is opposite the table surface so that a core mould box placed on the table can be clamped: securely between the table and the bottom of the sand. containing magazine by the forcing of the table upwardly by the piston and bell-crank means already described. This upward movement need only be small since the sand container will be set to suit the depth of the box, and it is only the clamping and sealing: of the box against the pressure and. delivery plate of the sand magazine that has to be effected" by the table movement.

The upper part of each pillar 24 is enclosed in a cylinder 31, the lower end of which is bolted: to a stout flange 32 on the upper guide bearing 25 of the sand container or magazine HI, and this cylinder 3 I is closed above the top of the pillar by a plate 33" through which a small orifice 34, or

more than. one, will be provided. Above this per" forated closure plate an enlarged pressure chamber 35. is provided, the purpose of which is to re ceive a suitable fluid such as oil and provide an air space abovethe fluid to. which compressedair 3 can be led. The enlarged, ballon-like chamber 35 gives effective storage without increasing head room demands, and the restricted orifice ensures a slow, smooth movement and a dashpot eiTect, when pressure is released.

As there are two cylinders 3 I, one on each pillar 24 there are two enlarged pressure chambers 35 and a common connecting air pipe 33 between them can be provided with a compressed air lead 31 so that the pressures in the two chambers will be equalised above the level of the fluid therein. The oil may be inserted through a cock at 38 and drained when necessary by a tap 39 below the orifice 34 and above the point of maximum entry of the pillar 24.

The upper end or face of each pillar 24 is provided with a suitable removable piston face 40 to act as a piston against the walls of the cylinder 3|. If compressed air is admitted to the upper parts of the pressure chambers 35 when the clamping means on the sand container or magazine guides 25, 26, have been released, the air pressure will drive the oil through the small orifice 34 in the closure plate 33 of each and against the piston face 40 of the fixed pillar 24. By the reaction of this fluid between the piston face and the apertured plate 33 across the cylinder 3I each cylinder will be raised so as to lift the whole of the sand container or magazine assembly bod ily on the pillars 24 to any height required above the table. The assembly will then be clamped in the desired position by the clamps on the guides of the container or magazine I I.

The pressure plate I4 at the lower part of the sand container or magazine 'is bodily removable and bolted in place, and this plate will be provided with the necessary opening or openings through which sand may be driven by compressed air admitted to the container to blow the sand into the shaped cavities in the core box to fill the latter with the core sand and so mould the cores required.

The lower part of the container has an annular chambered part M in its Wall to which the compressed air connection is made at 42, Figure 2, and provided with an inlet valve 43. The handle 44 of this valve may be coupled to an air exhaust valve at 45 in the magazine so that when the inlet valve is closed the exhaust from the magazine is opened, and vice versa. Within this annular air belt M is arranged a perforated cylindrical plate 46 covered with a Wire gauze or like sleeve 4'! so that the air is split up into many fine streams or jets, and a thorough mixture of the compressed air with the sand takes place as the sand is agitated within the container by the mechanical agitator.

The agitator may consist of a hub 48 with skeleton arms 49 and paddles projecting from the hub and the hub is secured on a drive spindle 50 which is enclosed in bearing-bushes BI, 52, carried and enclosed by a stout elbow casting 53 which can be bolted securely against the side wall of the container or magazine bore, see Figure 4. The drive spindle 50 is provided with a bevel gear 54 driven by a similar bevel 55 on gear shaft 56 projecting from a speed reduction gear box of a suitable kind in which the input shaft is driven from an electric motor 58.

The motor 58 and its starter 59 is arranged above the magazine I I on a suitable platform and also secured on top of the magazine is the sand hopper or chute I2 from which the magazine is supplied with sand.

After the oil pressure chambers or balloons 35 at the top of the pillar cylinder 3| have been subjected to air pressure to raise the sand maga- Zinc II to a given height for a particular box,

'or series of boxes, and the magazine bearings have been clamped securely in that position, a core box has been inserted, and the table raised by admitting compressed air in the cylinder I6 above the table piston I5 to clamp the box and make a sandtight joint between the openings in the pressure plate I4 and those in the core box, the air pressure is admitted to the annular chamber 4| above the pressure plate and the motor 58 is startedto drive the agitator arms 49 and paddles and the core or cores in the box is/are rapidly blown and so formed. The table cylinder I6 is then exhausted and the table I3 moves down under gravity reinforced by the spring 23 and returns the bell crank I8 and piston I5. The filled box is then removed.

If the box height is to be varied the air pressureabove the oil in the pressure chambers or -balloons" 35 is released and, after the' clamps are slackened, the sand magazine with itsagitator and motor unit will'return slowly down the pillars '24, the oil being forced up through the restricted passages 34, in the closure plates 33 in the cylinders 3 I The control of the machine may be made very simple by arranging the compressed air supply leads to be brought toa suitable multi-way control cook 60 for distribution to the table cylinder, the pressure chambers or balloons, and the annular chamber 4|. This point is arranged adjacent to the agitator motor switch so that the controls for the table or base, and the motor, may be all assembled Within easy reach of an operative. The part seen at BI is a free jet for cleaning purposes. 62 is a pressure gauge.

We claim:

1. Core making or blowing machine having a container for sand, means including a table for supporting-a core box below the container, an apertured pressure and sand delivery plate at the base of the container, means for supplying air under pressure to the container for forcing sand through said apertured plate into the core box, a pair of pillars disposed one at each end of the table, means for guiding the container on the pillars and means for clamping it thereon, a pair of cylinders secured to the container and capable of sliding on the pillars each of which pillars is adapted to act as a fixed piston in one of said cylinders, combined pneumatic and hydraulic means whereby fluid pressure may be admitted to the cylinders above the piston faces of the pillars for raising said container thereon, and means fixedly mounted in each cylinder above the pillars to form a restricted passageway for the passage of fluid from the upper part to the lower part of the cylinder, which means act as dashpots to give a smooth and slow action during ascent and descent of the cylinders and the container.

2. Core making or blowing machine having a container for sand, means including a table for supporting a core box below the container, an apertured pressure and sand delivery plate at the base of the container, means for supplying air under pressure to the container for forcing sand through said apertured plate into the'core box, a pair of pillars disposed one at each end of the table, means for guiding the container on the pillars and means for clamping it thereon, a pair of cylinders secured to the container and capable of sliding on the pillars, each of which pillars is adapted to act as a fixed piston in one of the cylinders, an enlarged vessel containing.

a supply of liquid arranged above each of said cylinders, each of said vessels being provided with a fixed apertured closing plate between the vessels and the top of the cylinder which serves as a dashpotto give a. smooth and slow action during ascent and descent of said cylinders, and

5 sand container upon the pillars.

DAVID HOWARD WOOD. .HERBE'RT JAMES ROE. 

